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How to reorder data.table columns (without copying)
I'd like to reorder columns in my data.table x , given a character vector of column names, neworder :
2 Answers
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Saving timestamp in mysql table using php
I have a field in a MySQL table which has a timestamp data type. I am saving data into that table. But when I pass the timestamp ( 1299762201428 ) to the record, it automatically saves the value 0000-00-00 00:00:00 into that table.
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How to select unique records by SQL
When I perform "SELECT * FROM table" I got results like below:
8 Answers
8
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How to align center the text in html table row?
I am using an HTML <table> and I want to align the text of <td> to the center in each cell.
7 Answers
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SQL Server loop - how do I loop through a set of records
...EGIN
SET @MyCursor = CURSOR FOR
select top 1000 YourField from dbo.table
where StatusID = 7
OPEN @MyCursor
FETCH NEXT FROM @MyCursor
INTO @MyField
WHILE @@FETCH_STATUS = 0
BEGIN
/*
YOUR ALGORITHM GOES HERE
*/
FETCH NEXT FROM...
Want to find records with no associated records in Rails
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Just imagine you have 10000000 records in friends table. What about performance in that case?
– goodniceweb
Dec 20 '16 at 14:51
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How to join (merge) data frames (inner, outer, left, right)
...f performance is a major issue for you, you should also look into the data.table package - that's a whole new set of join syntax, but it's radically faster than anything we're talking about here.
– Matt Parker
Feb 12 '13 at 16:22
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Center image in table td in CSS
I've been trying to align an image to the center of the table td. It worked with setting margin-left to a specific value but it also increased the size of td too and that isn't exactly what I wanted
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When is SQLiteOpenHelper onCreate() / onUpgrade() run?
I have created my tables in my SQLiteOpenHelper onCreate() but receive
15 Answers
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EF Code First “Invalid column name 'Discriminator'” but no inheritance
I have a table in my database called SEntries (see below the CREATE TABLE statement). It has a primary key, a couple of foreign keys and nothing special about it. I have many tables in my database similar to that one, but for some reason, this table ended up with a "Discriminator" column on the EF P...